TWI763998B - Exposure method, exposure apparatus, and method of manufacturing article - Google Patents

Abstract

The present invention provides an exposure method of exposing a substrate via an original held by a stage while scanning the original, comprising: performing a first step of scan-driving the stage so that a maximum acceleration becomes a first acceleration; and performing a second step of scan-driving the stage while exposing the substrate so that the maximum acceleration becomes a second acceleration after the performing the first step, wherein the first acceleration is lower than the second acceleration.

Description

Exposure method, exposure apparatus, and method of manufacturing articles

The present invention relates to an exposure method, an exposure apparatus, and a method of manufacturing an article.

As one type of apparatus used in manufacturing steps (lithography steps) of semiconductor devices, displays (FPDs), etc., there is known an exposure apparatus that exposes (scans and exposes) a substrate while relatively scanning-driving an original plate and a substrate , and transfer the original pattern to the substrate. In such an exposure apparatus, since the holding state between the original plate and the substrate (for example, immediately after the stage holds the original plate (or the substrate)) is not complete, an inertial force acting on the original plate when the stage is driven may be This will cause the position of the master to fluctuate (slip) relative to the table. Japanese Patent Laid-Open No. 2015-231035 discloses a technique for performing preliminary driving of a stage with a maximum acceleration equal to the maximum acceleration at the time of scanning exposure before scanning exposure of a substrate, so as to improve the gap between the master (reticle) and the stage by improving the The original plate is fixed to the table in the holding state.

For the exposure apparatus, the error between the position where the original plate is fixed on the stage by driving the stage and the target position where the original plate is to be arranged on the stage is ideally small.

The present invention provides, for example, a technique that facilitates securing a master to a table.

According to an aspect of the present invention, there is provided an exposure method of exposing a substrate via a master plate while scanning a master plate held by a stage, the exposure method comprising: performing a first step of scanning the drive stage so that the maximum acceleration becomes the first acceleration; and After the first step is performed, the second step of scanning the drive stage while exposing the substrate is performed so that the maximum acceleration becomes the second acceleration, wherein the first acceleration is lower than the second acceleration.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings.

Exemplary embodiments of the present invention will be described below with reference to the accompanying drawings. It should be noted that the same reference numerals denote the same components in all the drawings, and a repeated description thereof will not be given.

<First Embodiment> A first embodiment according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a view showing the arrangement of an exposure apparatus 100 according to the present embodiment. The exposure apparatus 100 shown in FIG. 1 may be an exposure apparatus that exposes a substrate W (wafer) without liquid intervening between the projection optical system 2 and the substrate W, or may be an exposure apparatus that exposes a liquid between the projection optical system 2 and the substrate W A liquid immersion exposure apparatus that exposes the substrate W in the case of intervention. An exposure apparatus for transferring a circuit pattern of a semiconductor device onto a substrate using a master M (reticle or mask) on which the circuit pattern is formed will be described below.

The exposure apparatus 100 shown in FIG. 1 is a so-called scan and repeat method exposure apparatus (scanning exposure apparatus) that exposes the substrate W while the original plate M and the substrate W are relatively scan-driven. The exposure apparatus 100 may include an illumination optical system 1 , a projection optical system 2 , a master stage 3 movable while holding the master M, a substrate stage 4 movable while holding the substrate W, and a control unit C. The control unit C is formed of, for example, a computer including a CPU and a memory (storage unit), and controls each unit of the exposure apparatus 100 . The XYZ orthogonal coordinate system shown in FIG. 1 may be defined such that the plane defined by the X and Y directions is parallel to the surface of the substrate W, and the Z direction is perpendicular to the surface of the substrate W.

The illumination optical system 1 shapes the light emitted from the light source 5 into, for example, strip-shaped or arc-shaped light, and illuminates a part of the master M with the shaped light. Although a KrF excimer laser emitting light having a wavelength of 248 nm can be used as the light source 5, a mercury lamp, an ArF excimer laser (with a wavelength of 193 nm), an EUV light source, and the like can also be used. The projection optical system 2 has a predetermined projection magnification, and projects a pattern of a portion of the original M that is illuminated by the illumination optical system 1 on a substrate (forms an image on the substrate).

The master table 3 includes a master chuck 3a, which holds the master M by, for example, vacuum suction, electrostatic suction, etc.; a master drive unit 3b, which drives the master M together with the master chuck 3a in the X and Y directions; and The reference plate 3c on which a mark indicating the reference position of the original plate table 3 is formed. The substrate stage 4 includes a substrate chuck 4a, which holds the substrate W by, for example, vacuum suction, electrostatic suction, etc.; a substrate driving unit 4b, which drives the substrate W in the X and Y directions together with the substrate chuck 4a; and The reference plate 4c has a mark indicating the reference position of the substrate stage 4 formed thereon. The master stage 3 and the substrate stage 4 are arranged such that the master M and the substrate W are positioned at almost optically conjugated positions (object plane and image plane of the projection optical system 2 ) via the projection optical system 2 .

The positions of the master stage 3 and the substrate stage 4 are measured by measuring units 10 and 12, respectively. The measurement unit 10 includes, for example, a laser interferometer, and can measure the laser light reflected by the strip mirror 11 when the laser light is emitted to the strip mirror 11 provided in the original stage 3 . Location. Similarly, the measurement unit 12 includes, for example, a laser interferometer, and can measure the substrate based on the laser light reflected by the strip mirror 13 when the laser light is emitted to the strip mirror 13 provided in the substrate stage 4 The location of stage 4.

During the scanning exposure of the substrate W, based on the pieces of positional information of the original stage 3 and the substrate stage 4 measured by the measurement units 10 and 12, respectively, the control unit C uses each other at a speed ratio corresponding to the projection magnification of the projection optical system 2 The original plate stage 3 and the substrate stage 4 are scanned and driven relatively in a synchronized manner. This can transfer the pattern of the master M onto the substrate (more precisely, the resist on the substrate).

The exposure apparatus 100 may further include an original plate position detection unit 14 (original plate alignment detection unit), a substrate position detection unit 15 (substrate alignment detection unit), and a surface position detection unit 16 . The original plate position detection unit 14 includes an alignment observer that detects the mark of the original plate M and the mark of the original plate table 3 arranged above the original plate position detection unit 14 by controlling the position of the original plate table 3 by the control unit C, and obtains the mark between the marks. relative position. For example, as shown in FIG. 2 , a plurality of marks 18 spaced apart in the X direction are set on the master table 3 (master chuck 3 a ), and the master position detection unit 14 detects each mark 17 of the master M and the master stage Each of the 3 marks 18. This enables the original plate position detection unit 14 to obtain the positional deviation (X, Y and θ directions) of the original plate M with respect to the original plate table 3 .

The substrate position detection unit 15 includes an alignment observer that detects a plurality of marks provided in a sample irradiated area among a plurality of irradiated areas in the substrate W, and obtains a plurality of marks in the substrate W by performing statistical processing on the detection results. array information of each irradiated area. The surface position detection unit 16 includes a projector 16a that projects light onto the surface of the substrate W and an optical receiver 16b that receives light reflected by the surface of the substrate W, and detects the height (in the Z direction) of the surface of the substrate W. Location). Referring to FIG. 1 , each of the original plate position detection unit 14 and the substrate position detection unit 15 is formed as an off-axis detection unit that detects each mark without the intervention of the projection optical system 2 . However, the present invention is not limited to this. For example, each unit may be formed as, for example, a TTL (Through The Lens) detection unit that detects each mark with the intervention of the projection optical system 2 .

In the exposure apparatus 100, the master M is arranged at a target position (a position where the master M is to be arranged) on the master stage 3 by a master conveying unit (not shown), and the master stage 3 holds the master M, thereby starting the substrate Scanning exposure of W. However, immediately after starting to hold the master M by the master table 3, the holding state between the master table 3 and the master M is incomplete. Therefore, if the master plate 3 is driven in this state, the inertial force acting on the master plate M may cause the position of the master plate M on the master plate 3 to fluctuate (slip). That is, the relative position between the target position on the original plate 3 and the original M may vary due to the scanning drive of the original plate 3 . Such fluctuation in the position of the master M is most likely to occur at the first scan drive of the master table 3 after the master M is started to be held, as shown in FIG. 3 , and also tends to become larger. On the other hand, if the scanning drive of the original plate 3 is repeated, the holding state of the original M is improved to fix the original M to the original table 3, thus reducing the positional fluctuation.

FIG. 4 is a view for explaining the principle of reducing the fluctuation of the position of the original plate M by repeating the scanning drive of the original plate table 3 . In FIG. 4 , 41 shows an enlarged view of a boundary portion between the master stage 3 and the master M, and 42 and 43 each show an enlarged view of a micro area in 41 in FIG. 4 . Further, 42 of FIG. 4 shows the case where the maximum acceleration when the original stage 3 is scan-driven is low, and 43 of FIG. 4 shows the case where the maximum acceleration when the original stage 3 is scan-driven is high.

In 41 to 43 of FIG. 4 , the views on the left side (immediately after holding start) each show a state immediately after the master M is arranged at the target position on the master table 3 and the master table 3 starts holding the master M. In this state, since the master M is supplied to and held by the master stage 3 while the master M is deformed and twisted, so-called chuck twist (vacuum twist or suction twist) occurs, and the master may exist microscopically A plurality of areas (gap) where M and the original plate 3 are not in contact with each other. That is, this state is a state in which the holding of the master M by the master stage 3 is not stable. On the other hand, if the scanning drive of the master stage 3 is performed only once, the inertial force acts on the master M to greatly reduce the chuck distortion, as shown in the central views (after the first drive) in 41 to 43 of FIG. 4 . This makes it possible to improve the holding state of the master M by the master table 3 . At this time, since the inertial force at the time of high acceleration shown at 43 of FIG. 4 is larger than the inertial force at the time of low acceleration shown at 42 of FIG. 4 , the position fluctuation tends to become larger. If the scanning drive of the original stage 3 is further performed, the original M can be fixed to the original stage 3, thereby further improving the holding state of the original M by the original stage 3, as shown in the right side views in 41 to 43 of FIG. after the first drive).

By repeating the scan drive of the master table 3 in this way, the holding of the master M by the master table 3 can be improved to fix the master M on the master table 3 . Therefore, in general, the exposure apparatus performs "preliminary scan driving" by scanning and driving the original plate 3 without exposing the substrate W for fixing the original M on the original plate 3 . The "preliminary scan drive" can be defined as driving the original stage 3 by the same movement stroke (movement range) as the movement stroke at the time of scanning exposure of the substrate W without stopping the original stage 3 . In addition, "preliminary scan driving" may be defined as performing scan driving of the original stage 3 under the same conditions as those at the time of scanning exposure of the substrate W (except for the acceleration of the original stage 3).

The error between the target position on the master stage 3 and the position of the master M fixed on the master stage 3 by the preliminary scanning drive (hereinafter sometimes referred to as "position deviation") can be determined by, for example, on the substrate W During the scanning exposure, the relative position between the original M and the substrate W is controlled to be corrected. However, the positional deviation is preferably small. For example, when the mark of the master M is arranged above the master position detection unit 14 , the control unit C drives the master stage 3 based on design information obtained by assuming that the master M is arranged at the target position on the master stage 3 . However, if the acceleration becomes equal to or higher than a predetermined value with respect to the holding force of the original plate M with respect to the master stage 3, the positional deviation may suddenly increase. Therefore, if the positional deviation is too large, the mark of the master M does not fall within the detection field of the master position detection unit 14, and it may become difficult to locate the master M. In this case, it takes time to search for the mark of the master M, which may be disadvantageous in terms of throughput.

In order to solve this problem, the exposure apparatus 100 according to the present embodiment performs the first step of scanning and driving the original stage 3 so that the maximum acceleration becomes the first acceleration, and the second step of scanning and driving the original stage 3 while exposing the substrate W , so that the maximum acceleration becomes the second acceleration. At this time, the first acceleration applied in the first step is set to be lower than the second acceleration applied in the second step. This can reduce the error (position deviation) between the target position of the original plate M on the original plate table 3 and the fixed position. The second acceleration is the maximum acceleration of the original stage 3 in the recipe preset to perform the scanning exposure of the substrate W, and may be, for example, set so that the time taken for the scanning exposure of one shot area is equal to or shorter than a desired value The maximum acceleration of the original table 3.

As shown in FIG. 3 , the positional fluctuation of the original plate M on the original plate table 3 tends to be large due to the first scan drive of the original plate table 3 after the original plate M is started to be held by the original plate table 3 . Therefore, the first step preferably includes the first scan drive of the master table 3 after the master M is started to be held. It should be noted that the "scanning drive of the original stage 3" used in the following description is defined as driving the original stage 3 in one direction with the same movement stroke as that at the time of scanning exposure of the substrate W.

FIG. 5 is a timing chart showing an example of scanning driving of the original plate stage 3 in the exposure apparatus 100 according to the present embodiment. In FIG. 5 , the abscissa represents time, and the ordinate represents the acceleration of the original stage 3 . Each of the driving steps A to G shown in FIG. 5 includes reciprocating driving of the original stage 3 with the same movement stroke as that at the time of scanning exposure of the substrate W. As shown in FIG. More specifically, as shown in FIG. 6, one driving step includes scanning driving 20 of the original plate 3 in a predetermined direction (eg, +Y direction), and in a direction opposite to the predetermined direction (eg, -Y direction) The scan driver 21 of the original plate stage 3 is provided. The scan drive 20 of the original plate 3 in the predetermined direction includes an acceleration operation D1 and a deceleration operation D2, and the scan drive 21 of the original plate 3 in the opposite direction includes an acceleration operation D3 and a deceleration operation D4. With respect to each acceleration operation (each deceleration operation), it is preferable to provide a constant acceleration period 22 (constant deceleration period) in consideration of the reproducibility of the positional fluctuation of the master M.

In the example shown in FIG. 5 , after the holding of the master M is started, the driving steps A and B of performing the scanning drive of the master stage 3 are performed so that the maximum acceleration becomes the first acceleration a ₁ . After the driving steps A and B, the driving steps C to G for performing the scanning driving of the original stage are performed so that the maximum acceleration becomes the second acceleration a ₂ . As described above, the _first acceleration a1 is set to a lower value than the _second acceleration a2.

In the example shown in FIG. 5, the time to start the scanning exposure of the substrate W is indicated by arrows 23a to 23d. For example, if the scanning exposure of the substrate starts from the driving step E (as indicated by the arrow 23a), the driving steps A and B applying the _first acceleration a1 and the driving steps C and D applying the _second acceleration a2 correspond to preliminary Scan driver. Further, if the scanning exposure of the substrate W starts from the driving step C (as indicated by the arrow 23b), the driving steps A and B applying the _first acceleration a1 correspond to the preliminary scanning driving. Similarly, if the scanning exposure of the substrate W starts from the driving step B (as indicated by the arrow 23c), the driving step A applying the _first acceleration a1 corresponds to the preliminary scanning driving. The scanning exposure of the substrate W can be started from the driving step A of performing the first scanning driving of the original plate stage 3 after the holding of the original plate M is started, as indicated by the arrow 23d. In this case, the preliminary scan driving is not performed, but the first acceleration a ₁ is applied in the driving step A. Therefore, compared to the case where the _second acceleration a2 is applied, the positional fluctuation (slip) of the original plate M on the original plate stage 3 is smaller, and the influence on the accuracy of transferring the pattern to the substrate is smaller.

Next, a method of setting the first acceleration will be described. The first acceleration can be set by the control unit C based on, for example, information representing the relationship between the positional fluctuation of the master M and the maximum acceleration at the first scan drive of the master stage 3 after starting to hold the master M. FIG. 7 is a graph showing the relationship (solid line) between the positional fluctuation of the original plate M and the maximum acceleration at the time of the first scan drive of the original plate stage 3 . This relationship can be obtained from experiments, simulations, and the like. For example, based on the information shown in FIG. 7 , the first acceleration is preferably determined within the range of the maximum acceleration that allows the positional fluctuation of the original plate M on the original plate table 3 to fall within the allowable range AR. The allowable range AR can be arbitrarily set based on the arrangement of the master stage 3 or the exposure apparatus itself, and can be input by the user via the user interface. The allowable range AR can be set to, for example, the size (eg, radius) of the detection field of the master position detection unit 14 .

If the first acceleration is too low, the effect of reducing the twist of the chuck is insufficient. If the first acceleration is too high, the positional fluctuation of the master M may become larger. The first acceleration is preferably determined in consideration of the reproducibility of the positional fluctuation of the master M. FIG. 8 shows the results of experiments conducted on the fluctuation of the position of the master M in the first scan drive of the master stage 3 while changing the maximum acceleration. FIG. 8 shows that the position of the master M at each of the three accelerations A to C that may be candidates for the first acceleration fluctuates relative to each of the different masters M1 and M2 . Each data is obtained by arranging the master on the master stage 3 and performing each step of scanning and driving the master stage 3 . As an example, acceleration A is set to 80% of the second acceleration (a value of -1G lower than the second acceleration), acceleration B is set to 60% of the second acceleration (a value of -2G lower than the second acceleration), and The acceleration C is set to 40% of the second acceleration (a value lower than the second acceleration by -3G).

As shown in FIG. 8 , it should be understood that, under acceleration A, the positional fluctuation of master M in each of profiles 1 to 4 greatly exceeds allowable values with respect to both masters M1 and M2. Under the acceleration B, the position fluctuation of the original M1 is almost the same as that under the acceleration A, and greatly exceeds the allowable value, and compared with the acceleration A, the position fluctuation of the original M2 under the acceleration B is reduced, but still exceeds the allowable value. allowance. Regarding the original M2 under acceleration B, the positional fluctuations in the materials 1 to 5 vary greatly, and the reproducibility is poor. On the other hand, under the acceleration C, the positional fluctuation of the master M in each of the materials 1 to 5 is equal to or less than the allowable value with respect to both the masters M1 and M2, and the reproducibility is satisfactory. Therefore, based on the experimental results shown in FIG. 8 , the acceleration C is preferably set as the first acceleration. If the scanning drive of the master table (the first step) is performed too many times at the first acceleration, it is disadvantageous in terms of throughput. On the other hand, if the number of times is too small, the chuck twist cannot be reduced within the allowable range. Based on experimental results, the number of times of the first step is preferably set to, for example, four to ten.

Next, the control procedure of the exposure apparatus 100 according to the present embodiment will be described. FIG. 9 is a flowchart illustrating a control procedure of the exposure apparatus 100 according to the present embodiment. Each step of the control program shown in FIG. 9 may be executed by the control unit C. As shown in FIG. An example of performing the scan drive of the original stage 3 at the first acceleration and the scan drive of the original stage 3 (as the preliminary scan drive) at the second acceleration will be described with reference to the control program shown in FIG. 9 .

In step S11 , the control unit C causes a master conveying unit (not shown) to convey the master M to a target position on the master table 3 . In step S12 , the control unit C causes the substrate conveyance unit (not shown) to convey the substrate W onto the substrate stage 4 . In step S13, as a preliminary scan drive, the control unit C scan-drives the original stage 3 so that the maximum acceleration becomes the first acceleration (first step). In step S14, as a preliminary scan drive, the control unit C scan-drives the original stage 3 so that the maximum acceleration becomes the second acceleration (third step). In this embodiment, the second acceleration is applied in step S14. However, the present invention is not limited thereto, and a third acceleration higher than the first acceleration and lower than the second acceleration may be applied.

In step S15 , the control unit C causes the original plate position detection unit 14 to measure the positional deviation (error) of the original plate M with respect to the target position on the original plate table 3 . More precisely, when the control unit C can control the original plate 3 so that the mark of the original M and the mark of the original plate 3 are arranged above the original position detection unit 14 and cause the original position detection unit 14 to detect the relative positions between the marks, Position deviation can be measured.

In step S16, the control unit C determines whether the master M is fixed to the master table 3, that is, whether the positional fluctuation of the master M on the master table 3 falls (consolidates) within an allowable range. For example, the control unit C obtains the difference between the positional deviation of the original M which is currently measured in step S15 and the positional deviation of the original M that was previously measured in step S15. If the difference falls within the allowable range, the control unit C determines that the master M is fixed to the master table 3 . If it is determined that the master M is not fixed, the process proceeds to step S17 to change the conditions of the preliminary scan driving, and then steps S14 to S16 are performed again. On the other hand, if it is determined that the master M is fixed, the process proceeds to step S18. In step S18 , the control unit C starts scanning exposure for each of the plurality of shot regions in the substrate W. In the scanning exposure of each shot area, scanning driving of the original stage 3 is performed so that the maximum acceleration becomes the second acceleration (second step).

A detailed example of the control program shown in FIG. 9 will now be described. For example, as shown in FIG. 5 , the positional deviation of the original plate M is measured at the measurement time point 24 , the reciprocating driving of the original plate table 3 is performed (two scan driving operations), and then the positional deviation of the original plate M is measured at the measurement time point 25 . The difference between the position deviations measured at the measurement time points 24 and 25 is obtained, and it is determined whether this difference falls within the allowable range. If the difference falls outside the allowable range, it is determined that the original M is not fixed to the original stage 3, and the conditions of the preliminary scanning driving are changed to perform the scanning driving of the original stage 3 again, thereby measuring at the measurement time point 26 The positional deviation of the original M. If the difference between the positional deviations measured at the measurement time points 25 and 26 falls within the allowable range, it is determined that the original M is fixed on the original stage 3, and the scanning exposure of the substrate W is started. Examples of the conditions of the preliminary scan drive are the number of scan drives of the original stage 3 and the maximum acceleration of the original stage 3 . In the example shown in FIG. 5 , as a condition of the preliminary scan drive, the number of scan drives of the original stage 3 is changed from two times for the reciprocating drive to one time for the unidirectional drive.

As described above, the exposure apparatus 100 according to the present embodiment performs the first step of scanning and driving the original stage 3 so that the maximum acceleration becomes the first acceleration; and the second step of scanning and driving the original stage 3 while exposing the substrate W, so that The maximum acceleration becomes the second acceleration. At this time, the first acceleration applied in the first step is made lower than the second acceleration applied in the second step. This can reduce the error (position deviation) between the target position of the original plate M on the original plate table 3 and the fixed position.

<Second Embodiment> A second embodiment according to the present invention will be described. In the second embodiment, as shown in FIG. 1, a detection unit 6 is provided, which detects the holding force of the original plate 3 (original chuck 3a) on the original M, and the first step (scanning and driving the original plate 3 with the first acceleration) ) ends according to the detection result of the holding force of the master M by the detection unit 6 . The holding force of the master M is, for example, vacuum suction pressure or electrostatic suction pressure. It should be noted that the arrangement of the exposure apparatus according to the present embodiment is the same as that in the first embodiment, and the description thereof will be omitted.

A control procedure of the exposure apparatus according to the present embodiment will be described with reference to FIGS. 10 and 11 . FIG. 10 shows a time chart of the temporal change of the holding force of the original plate M detected by the detection unit 6 and an example of the scanning drive of the original plate stage 3 . FIG. 11 is a flowchart illustrating a control procedure of the exposure apparatus according to the present embodiment. Each step of the control program shown in FIG. 11 may be executed by the control unit C.

In step S21 , the control unit C causes the master conveying unit (not shown) to convey the master M to a target position on the master table 3 . In step S22 , the control unit C causes the substrate conveyance unit (not shown) to convey the substrate W onto the substrate stage 4 . In step S23, the control unit C determines whether or not the holding force of the master M detected by the detection unit 6 exceeds the first threshold value TH ₁ . If the holding force of the master M does not exceed the first threshold value TH ₁ , step S23 is repeatedly executed; otherwise, the process proceeds to step S24 . In step S24, the control unit C performs scan driving of the original stage 3 (first step) so that the maximum acceleration becomes the first acceleration.

In a state in which insufficient holding force of the original plate M by the original plate 3 is hardly generated, even if a relatively low first acceleration is applied to the scanning drive of the original plate 3, the positional fluctuation (slip) of the original M on the original plate 3 is likely to fluctuate (slip). become larger. In order to solve this problem, in this embodiment, a _first threshold value TH1 is provided, and when the holding force of the original plate M exceeds the first threshold value TH1, the original plate table 3 is scanned and driven with the _first acceleration (first step). Immediately after the holding of the master M starts, the holding force of the master M changes with a steep gradient, but the gradient becomes gentle at a predetermined value. The _first threshold value TH1 can be arbitrarily set, but it is preferably set to such a change point of the gradient. For example, the _first threshold value TH1 may be set to a value falling within a range of 40% to 60% of the value obtained when the holding force of the master M is in a stable state.

In step S25, the control unit C determines whether or not the holding force of the original M detected by the detection unit 6 exceeds a _second threshold value TH2 larger _than the first threshold value TH1. If the holding force of the master M does not exceed the second threshold value TH ₂ , the process returns to step S24 to perform the scanning drive of the master stage 3 again at the first acceleration. On the other hand, if the holding force of the original plate M exceeds the second threshold value TH ₂ , the process proceeds to step S26 to end the scanning driving of the original plate table 3 at the first acceleration, and perform the scanning driving of the original plate table 3 such that the maximum acceleration becomes the second acceleration. The _second threshold value TH2 may be arbitrarily set, and may be set to, for example, a value falling within a range of 80% to 95% of the value obtained when the holding force of the master M is in a stable state.

In step S27, the control unit C determines whether or not the scanning driving of the original stage 3 at the second acceleration has been performed a predetermined number of times. If the scanning driving of the original stage 3 at the second acceleration has not been performed a predetermined number of times, the process returns to step S26 to perform the scanning driving of the original stage 3 at the second acceleration again. On the other hand, if the scanning driving of the master stage 3 at the second acceleration has been performed a predetermined number of times, the process proceeds to step S28. In step S28, the control unit C starts scanning exposure for each of the plurality of shot regions in the substrate W. In the scanning exposure of each shot area, scanning driving of the original stage 3 is performed so that the maximum acceleration becomes the second acceleration (second step).

As described above, in this embodiment, the maximum acceleration at the time of scanning driving of the master table 3 is changed according to the holding force of the master table 3 to the master M. This makes it possible to perform scan driving of the master table 3 at the maximum acceleration according to the holding force of the master M, and thus it is possible to prevent the positional fluctuation of the master M on the master table 3 from occurring excessively. In this embodiment, two threshold values for changing the maximum acceleration at the time of scanning driving of the original stage 3 are set. However, three or more thresholds may be provided, and the maximum acceleration may be changed in steps. The maximum acceleration can be continuously changed according to the holding force of the master M.

<Third Embodiment> A third embodiment according to the present invention will be described. In the third embodiment, the number of times of scanning driving of the original stage 3 is counted, and the first step (scanning and driving the original stage 3 at the first acceleration) ends according to the counted number of times. It should be noted that the arrangement of the exposure apparatus according to the present embodiment is the same as that in the first embodiment, and the description thereof will be omitted.

A control procedure of the exposure apparatus according to the present embodiment will be described with reference to FIGS. 12 and 13 . FIG. 12 is a timing chart showing an example of scan driving of the original stage 3 . FIG. 13 is a flowchart illustrating a control procedure of the exposure apparatus according to the present embodiment. Each step of the control program shown in FIG. 13 may be executed by the control unit C. It should be noted that steps S31 and S32 are the same as steps S21 and S22 of the control routine shown in FIG. 11 described in the second embodiment.

In step S33, the control unit C executes the scanning driving of the original stage 3 (first step) so that the maximum acceleration becomes the first acceleration while counting the number of times the scanning driving of the original stage 3 is performed at the first acceleration. In step S34, the control unit C determines whether or not the number of times of execution of the scan driving of the original stage 3 at the first acceleration has reached a predetermined number N. Based on, for example, experimental results, simulations, and the like, the predetermined number N may be set as the number such that the positional fluctuation of the original plate M caused by the scanning drive of the original plate table 3 falls within an allowable range. If the predetermined number N has not been reached, the process returns to S34 to perform the scanning driving of the original stage 3 at the first acceleration again; otherwise, the scanning driving of the original stage 3 at the first acceleration ends, and the process proceeds to step S35.

In step S35, the control unit C executes the scanning driving of the original stage 3 so that the maximum acceleration becomes the second acceleration, while counting the number of times the scanning driving of the original stage 3 is performed at the second acceleration. In step S36, the control unit C determines whether the number of times of execution of the scan driving of the original stage 3 at the second acceleration has reached a predetermined number M. Based on, for example, experimental results, simulations, etc., the predetermined number M may be set such that the positional fluctuation of the original plate M caused by the scanning drive of the original plate table 3 falls within an allowable range. If the predetermined number M has not been reached, the process returns to S35 to perform the scanning driving of the original stage 3 with the second acceleration again; otherwise, the scanning driving of the original stage 3 with the second acceleration ends, and the process proceeds to step S37. In step S37 , the control unit C starts scanning exposure for each of the plurality of shot regions in the substrate W. In the scanning exposure of each shot area, scanning driving of the original stage 3 is performed so that the maximum acceleration becomes the second acceleration (second step).

As described above, in this embodiment, the maximum acceleration at the time of the scanning driving of the original stage 3 is changed according to the number of executions of the scanning driving of the original stage 3 at the first acceleration. Also in this control process, the positional fluctuation of the original plate M on the original plate table 3 can be prevented from occurring excessively.

In this embodiment, the maximum acceleration is changed according to the number of times the scan drive of the original stage 3 is performed. However, for example, the maximum acceleration may be changed according to the time during which the scanning driving of the original stage 3 is performed. More precisely, the time during which the scanning driving of the original stage 3 is performed at the first acceleration is measured. When the time reaches the first threshold value, the scanning driving of the original plate 3 at the first acceleration is ended (the first step), and the scanning driving of the original table 3 at the second acceleration is started. Next, the time during which the scan driving of the original stage 3 was performed at the second acceleration was measured. When the time reaches the second threshold, the scanning drive of the original plate stage 3 at the second acceleration is terminated, and the scanning exposure of the substrate is started.

<Example of a method of manufacturing an article> The method of manufacturing an article according to an embodiment of the present invention is suitable for manufacturing, for example, a microdevice such as a semiconductor device, or an article having a microstructured element. The method of manufacturing an article according to the present embodiment includes a step of forming a latent image pattern on a photosensitizer applied to a substrate using the above-described exposure device (a step of exposing the substrate); and developing (a step of exposing the substrate) using the latent image pattern formed in the above step. processing) the step of the substrate. This fabrication method also includes other known steps (oxidation, deposition, vapor deposition, doping, planarization, etching, resist separation, dicing, bonding, packaging, etc.). Compared with the conventional method, the method of manufacturing the article according to the present embodiment is advantageous in at least one of the performance, quality, productivity and production cost of the article.

<Other Embodiments> Embodiments of the present invention can also be implemented by a computer of the system or device, the computer reads and executes the data recorded in the storage medium (which may also be more fully referred to as "non-transitory computer-readable"). computer-executable instructions (eg, one or more programs) on a storage medium") for performing, and/or including functions for performing one or more of the above-described embodiments one or more circuits (eg, application-specific integrated circuits (ASICs)), and embodiments of the invention may be implemented by a computer of a system or device to, for example, read and execute computer-executable instructions from a storage medium to Implemented in a method that performs the functions of one or more of the above-described embodiments, and/or controls one or more circuits to perform the functions of one or more of the above-described embodiments. A computer may include one or more processors (eg, a central processing unit (CPU), a micro processing unit (MPU)), and may include a single computer or a network of individual processors to read and execute computer executables instruction. Computer-executable instructions, for example, may be provided to the computer from a network or storage medium. Storage media may include, for example, hard disks, random access memory (RAM), read only memory (ROM), storage for distributed computing systems, optical discs (eg, compact discs (CDs), digital compact discs (DVD) or Blu-ray Disc (BD) ^™ ), one or more of a flash memory device, a memory card, and the like.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

1‧‧‧Illumination optical system 2‧‧‧Projection optical system 3‧‧‧Master stage 3a‧‧‧Master chuck 3b‧‧‧Master drive unit 3c‧‧‧Reference plate 4‧‧‧Substrate stage 4a‧‧‧ Substrate chuck 4b‧‧‧Substrate driving unit 4c‧‧‧Reference plate 5‧‧‧Light source 6‧‧‧Detecting unit 10‧‧‧Measurement unit 11‧‧‧Strip mirror 12‧‧‧Measurement unit 13‧‧ ‧Strip mirror 14‧‧‧Original plate position detection unit 15‧‧‧Substrate position detection unit 16‧‧‧Surface position detection unit 16a‧‧‧Projector 16b‧‧‧Optical receiver 17‧‧‧Marking 18‧‧ ‧Mark 20‧‧‧Scanning Drive 21‧‧‧Scanning Drive 22‧‧‧Constant Acceleration Period 23a‧‧‧Arrow 23b‧‧‧Arrow 23c‧‧‧Arrow 23d‧‧‧Arrow 24‧‧‧Measurement Time Point 25 ‧‧‧Measurement time point 26‧‧‧Measurement time point 41‧‧‧Enlarged view of boundary portion 42‧‧‧Enlarged view of micro area 43‧‧‧Enlarged view of micro area 100‧‧‧Exposure device a ₁ ‧‧ ‧First acceleration a ₂ ‧‧‧Second acceleration AR‧‧‧Allowable range C‧‧‧Control unit D1‧‧‧Acceleration operation D2‧‧‧Deceleration operation D3‧‧‧Acceleration operation D4‧‧‧Deceleration operation M ‧‧‧Original S11‧‧‧Step S12‧‧‧Step S13‧‧‧Step S14‧‧‧Step S15‧‧‧Step S16‧‧‧Step S17‧‧‧Step S18‧‧‧Step S21‧‧‧Step S22 ‧‧‧Step S23‧‧‧Step S24‧‧‧Step S25‧‧‧Step S26‧‧‧Step S27‧‧‧Step S28‧‧‧Step S31‧‧‧Step S32‧‧‧Step S33‧‧‧Step S34 ‧‧‧Step S35‧‧‧Step S36‧‧‧Step S37‧‧‧Step TH ₁ ‧‧‧First Threshold TH ₂ ‧‧‧Second Threshold W‧‧‧Substrate

FIG. 1 is a view showing the arrangement of an exposure apparatus 100;

FIG. 2 is a view showing the master table holding the master when viewed from above;

3 is a graph showing the relationship between the number of scan drives and the positional fluctuation of the original plate;

FIG. 4 is a view for explaining the principle of reducing the positional fluctuation of the master;

FIG. 5 is a timing chart showing an example of scan driving of the original stage according to the first embodiment;

6 is a timing chart showing the operation of the master stage in one driving step;

FIG. 7 is a graph showing the relationship between the positional fluctuation of the original plate and the maximum acceleration at the time of the first scan drive of the original plate stage;

FIG. 8 is a view showing the result of an experiment on the positional fluctuation of the master at the time of the first scan drive of the master stage when the maximum acceleration is changed;

9 is a flowchart illustrating a control procedure of the exposure apparatus according to the first embodiment;

FIG. 10 is a timing chart showing an example of scan driving of the master stage according to the second embodiment;

11 is a flowchart illustrating a control procedure of the exposure apparatus according to the second embodiment;

FIG. 12 is a timing chart showing an example of scan driving of the original stage according to the third embodiment; and

13 is a flowchart illustrating a control procedure of the exposure apparatus according to the third embodiment.

Claims (17)

An exposure method for exposing a substrate via the original while scanning a master held by a stage, the exposure method comprising: performing a first step of scanning and driving the stage without exposing the substrate so that the maximum acceleration is a first acceleration; and after performing the first step, performing a second step of scanning and driving the stage while exposing the substrate such that the maximum acceleration is a second acceleration, wherein the first acceleration is lower than the second acceleration, and Wherein, the number of times of scanning and driving the stage in the first step is ten or less. The exposure method as described in claim 1, wherein the first step comprises scanning and driving the stage for the first time after starting to hold the master by the stage. The exposure method of claim 1, further comprising, after performing the first step and before performing the second step, performing a third step of scanning and driving the stage without exposing the substrate, so that The maximum acceleration is a third acceleration higher than the first acceleration. The exposure method of claim 3, wherein the third acceleration is lower than the second acceleration. The exposure method described in item 1 of the claimed scope further comprises, before performing the second step, determining whether the positional fluctuation of the original plate on the stage caused by the scanning drive of the stage falls within an allowable range, Wherein, when it is determined that the position fluctuation of the original plate falls within the allowable range, the second step is started. The exposure method as described in claim 5, wherein the maximum acceleration is changed when it is determined that the positional fluctuation of the original plate falls outside the allowable range, and the scanning drive is performed without exposing the substrate the station. The exposure method according to claim 1, wherein the execution of the first step is ended according to a result of detecting the holding force of the stage for the original plate. The exposure method as described in claim 7, wherein after the stage starts to hold the master, in the case where the result of detecting the holding force of the master exceeds a first threshold, the first step is started, and When the result of detecting the holding force of the original plate exceeds a second threshold value greater than the first threshold value, the execution of the first step is ended. The exposure method according to claim 1, wherein, according to The execution of the first step is ended when the number of execution times of the scanning drive of the stage when the first step is executed. The exposure method according to claim 1, wherein the execution of the first step is terminated according to the time during which the first step is executed. The exposure method according to claim 1, wherein when the first step is performed, the stage is scanned and driven with the same movement stroke as when the second step is performed. The exposure method of claim 1, wherein the number of times of scanning and driving the stage in the first step falls within a range from four to ten. The exposure method of claim 1, wherein the first acceleration is set to be 50% of the second acceleration. The exposure method of claim 1, wherein the first acceleration is set to be 40% of the second acceleration. The exposure method of claim 1, wherein the scanning-driving of the stage in each of the first step and the second step includes an acceleration operation and a deceleration operation, the acceleration operation having a constant acceleration period, During the constant acceleration period, the acceleration of the table is constant, and the deceleration operation The operation has a constant deceleration period during which the deceleration of the table is constant. An exposure device for exposing a substrate via the original plate while scanning the original plate, the exposure device comprising: a stage configured to move while holding the original plate; and a control unit configured to control the substrate without exposing the substrate scanning driving of the stage such that the maximum acceleration is a first acceleration, and then controlling the scanning driving of the stage while exposing the substrate such that the maximum acceleration is a second acceleration, wherein the first acceleration is lower than the second acceleration, And wherein, the number of times of scanning driving of the stage without exposing the substrate is ten or less. A method of manufacturing an article, the method comprising: exposing a substrate using the exposure method of any one of claims 1 to 15; developing the exposed substrate; and treating the developed substrate to manufacture the thing.

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